The present invention relates to color image processing method and apparatus and, more particularly, to color image processing method and apparatus which can suppress any side effects of the chrominance emphasizing process.
Hitherto, for instance, in Hiroshi Tanaka, "The Image Processing Application Technique," The Kogyo Chosakai, a chrominance converting process for obtaining a chrominance emphasis image or a chrominance suppression image by performing chrominance conversion to an original color image is disclosed.
In short, the chrominance converting process intends to obtain R', G', and B' signals of the chrominance conversion image from R, G, and B signals of an original color image by the following equation (1). ##EQU1##
The technique to obtain the chrominance emphasis image by such a chrominance converting process is used in a color image processing apparatus such as color scanner, color television camera, color monitor, video recorder, color printer, or the like.
In the conventional color image processing apparatus, a chrominance converting process is executed for the entire original color image, thereby obtaining a chrominance emphasis image.
There is, however, a problem such that when the chrominance emphasizing process is executed in the case where there is a deviation of the balance of the R, G, and B signals of the original color image due to spectral characteristics of the sensor or the like, a side effect such that a color deviation becomes conspicuous in the portion of a small chrominance or luminousness occurs.